I don't really have any answers for you but I do want to chime in with my personal experience .

I am currently waiting for the second half of my root canal which will be in a couple of weeks. I had a tooth crack and apparently the nerve was dying within the tooth, and I didn't know this at the time and it was Christmas week and I had a house full of company- fun times! Not.
I went to the dentist the day after Christmas He took x-rays and did an exam and she discovered what it was, which I already mentioned above said I needed root canal and a crown. But he also said this is the type of situation that people derive horror stories about root canals from. So he was going to do the first half that day and the second half in a few weeks after the nerve finished dying off.
And how this pertains to you is- the first couple days when I didn't know what the heck was going on that side of my face had earache eye bone -socket ache, jaw, ache and ache just about everywhere including the tooth but all the other teeth too. My theory is that the inflammation from the dying tooth nerve was magnified 100 fold by my Sjogren's inflammation. Does that make any sense?
So I guess explore all possibilities, have your teeth checked. Have your sinuses checked because sometimes when we're sore from something the Sjogren's makes it sore in other places as well.
Again, this is just my experience as a patient. Really. I don't have an answer for you but that's what happened to me.
I wish you the best of luck!